1. Field of the Invention
The field of this invention relates to dissolution testing equipment for determining the dissolving rate of drugs encapsulated in the form of a tablet, capsule or caplet which are commonly known as pills.
2. Description of the Prior Art
Drugs are commonly manufactured in the form of pills. The reason for using pills is that when the drug is swallowed by a human, the drug will be disseminated into the body over a period of time as the pill dissolves. Manufacturers of pills are required by law to determine the precise dissolving characteristics of their pill before it is placed on the market. In order to determine the dissolving characteristics, dissolution test equipment are utilized. Although the apparatus is commonly used in conjunction with drugs designed for human consumption, it is considered to be within the scope of this invention to use it with other animals such as horses, cows, rabbits, cats, dogs, monkeys, etc.
Every known form of dissolution testing equipment utilizes one or more of liquid containing flasks. In that flask is to be placed a solution with that solution essentially duplicating the liquid solution that is contained within the stomach of the human body. A precise quantity of the solution is placed within the flask. The pill is then inserted within the flask with the time of the insertion then noted. A mixing paddle is inserted within the flask with mixing at a precise rate then occurring. The mixing procedure is to duplicate the natural turbulence that is created within the stomach of the human. Aliquots are removed from the solution at precise time intervals with these aliquots then being analyzed to determine the amount of drug that has been dissolved within the solution in relation to the time the pill has been in solution.
In order to insure that this testing process is accomplished as accurately as possible, such dissolution testing apparatus in the past has been designed as follows:
1. Normally the dissolution testing apparatus will have a plurality of flasks, such as six or eight. Dissolution testing of the pill is accomplished simultaneously in all six or eight flasks with each flask to receive a pill. The average dissolving rate is then calculated between the flasks.
2. The flasks are placed in a bath with this bath to be maintained at a precise temperature. The temperature level is to essentially duplicate the temperature of the stomach liquid within the human.
3. It is also important to achieve the precise turbulence in each of the flasks with it being understood that if a flask is encountering a greater amount of turbulence, that flask will typically have a faster dissolving rate. Therefore, each mixing paddle that is inserted within a flask must be exactly the same size and it must be precisely centered within that flask. Additionally, each mixing paddle must be rotated at precisely the same speed.
Further, it is desirable for dissolution test equipment to be "user friendly." Dissolution test equipment should be constructed so that it can be operated in a precise manner by relatively unskilled labor. Therefore when using unskilled labor, accurate dissolution test results can be obtained.
Also the operation of the testing equipment must be accomplished with ease and provide the user with the confidence that the tests are performed correctly.